Fig. 2. BrdU-positive cell, indicating mitotic activity within the last 18 h magnification: 650 in irradiated smooth muscle cells 22.5 Gy A; and untreated control B. The different number of BrdU-positive cells is clearly demonstrated.
Du¨sseldorf, Germany equipped with appropriate filter sets. The destruction of cytoskeletal components was
quantified in percent in comparison with untreated controls. For each investigation 100 cells were exam-
ined according to the following criteria: cytoskeletal structure ‘intact’ if the localisaton of smooth muscle-
actin, vimentin, and a-tubulin was completely normal and ‘changed’, if the structures were little or severely
destroyed.
2
.
6
. Statistical e6aluation Results are expressed as mean 9 standard deviation.
Statistical significance of differences between controls and irradiated cells was determined by paired t-test.
For comparisons between HCAEC and HCMSMC re- spectively HCAEC and HCPSMC the unpaired t-test
was used. Differences were considered significant at a value of P B 0.05.
3. Results
3
.
1
. Cell proliferation after irradiation Proliferation of HCAEC was not significantly inhib-
ited 18 h after irradiation with 7.5 and 15 Gy. After irradiation with 22.5, 30, and 37.5 Gy proliferation of
HCAEC was significantly inhibited in a dose dependent manner Table 1. HCPSMC reacted with a significant,
dose dependent reduction of cell proliferation after irradiation with 7.5 – 37.5 Gy Table 1. After irradia-
tion with 7.5 Gy the inhibitory effect was more than 45 P B 0.05; paired t-test, the maximal inhibitory
effect of 75 was found after irradiation with 37.5 Gy P = 0.004; paired t-test; Table 1. Proliferation of
HCMSMC was significantly inhibited in a dose depen-
Table 1 Comparison of BrdU-positive HCAEC, HCPSMC, and HCMSMC
18 h after irradiation to untreated controls mean 9 SD; paired t-test
a
HCAEC HCMSMC
Mean absorbed dose HCPSMC
82.9 9 10.3 7.5 Gy
53.2 9 13.6 58.8 9 7.4
n.s. PB0.05
PB0.01 n = 3
n = 4 n = 3
71.9 9 11.7 53.7 9 5.9
15 Gy 37.0 9 12.8
PB0.001 P = 0.01
n.s. n = 3
n = 3 n = 3
60.5 9 11.7 22.5 Gy
32.6 9 12.7 48.3 9 6.7
PB0.001 PB0.001
PB0.001 n = 6
n = 6 n = 8
31.8 9 0.8 46.7 9 5.3
30 Gy 51.1 9 3.5
P = 0.002 PB0.001
PB0.001 n = 3
n = 3 n = 4
46.7 9 1.8 40.4 9 4.7
26.8 9 7.6 37.5 Gy
PB0.001 PB0.001
PB0.001 n = 3
n = 3 n = 3
a
n.s., Not significant.
Table 2 Effect of irradation with rhenium-188 to the cytoskeletal structures of smooth muscle-a-actin, vimentin, a-tubulin, and the von vWF in HCPSMC,
HCMSMC, and HCAEC
a
HCMSMC HCPSMC
HCAEC 22.5 Gy
Control Control
22.5 Gy Control
22.5 Gy 8119
– –
– –
vWF 8218
– 8911
928 –
928 SM-a-actin
928 1000
a-Tubulin 1000
1000 955
1000 1000
1000 Vimentin
1000 1000
1000 1000
1000
a
A total of 100 cells per structure were evaluated regarding damage values given as unaffecteddamaged.
dent manner after irradition with 7.5 – 37.5 Gy Table 1, Fig. 2. After irradiation with 7.5 Gy an inhibitory
effect of more than 40 was found P = 0.002; paired t-test, the maximal inhibition of almost 60 was seen
after irradiation with 37.5 Gy P B 0.001; paired t-test; Table 1. HCAEC were significantly P B 0.05 less
radiosensitive
in comparison
to HCPSMC
and HCMSMC after irradiation with 7.5, 15, and 22.5 Gy.
After irradiation with 30 and 37.5 Gy a significantly decreased effect P B 0.001 and P B 0.01, respectively
of irradiation on HCAEC was seen in comparison to HCPSMC, differences in comparison to HCMSMC
were not statistically significant.
3
.
2
. Alterations after irradiation of cytoskeleton and the 6on Willebrand factor
The HCAEC were identified by detection of vWF, the HCPSMC and HCSMSC by binding of the anti-
body against smooth muscle a-actin. Eighteen hours after Re-188-irradiation with 22.5 Gy the localisation of
smooth muscle a-actin, vimentin and a-tubulin did not show any alteration in comparison to non-irradiated
cells Fig. 3; Table 2.
4. Discussion
